IB ESS Topic 6.2 Stratospheric ozone

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What is stratospheric ozone?

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Stratospheric ozone is a layer of ozone (O3) located in the stratosphere, approximately 20-30 km above the Earth's surface, that absorbs the majority of the sun's harmful ultraviolet (UV) radiation.

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What are chlorofluorocarbons (CFCs)?

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CFCs are man-made chemical compounds used in refrigeration, air conditioning, and aerosol propellants that contribute to ozone depletion when released into the atmosphere.

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What is the ozone layer's primary function?

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The primary function of the ozone layer is to absorb and block the majority of the sun's harmful ultraviolet (UV) radiation, protecting living organisms on Earth.

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What are HFCs and why are they a concern?

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Hydrofluorocarbons (HFCs) are chemicals that replaced CFCs in many applications. They are now a concern because they are potent greenhouse gases that contribute to global warming.

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What is the global distillation effect?

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The global distillation effect refers to the process by which volatile organic compounds, including ozone-depleting substances, are transported from warmer to cooler regions, leading to higher concentrations in polar areas.

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What is the relationship between ozone depletion and skin cancer?

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Ozone depletion leads to increased levels of UV radiation reaching the Earth's surface, which is linked to a higher incidence of skin cancer in humans.

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What are the main causes of ozone layer depletion?

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The main causes of ozone layer depletion include the release of CFCs, halons, and other ozone-depleting substances (ODS) into the atmosphere.

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What is the role of chlorine in ozone depletion?

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Chlorine atoms released from CFCs and other ODS catalyze the breakdown of ozone molecules, leading to ozone depletion in the stratosphere.

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What are the effects of increased UV radiation on ecosystems?

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Increased UV radiation can harm ecosystems by reducing photosynthetic activity in plants, affecting food chains, and damaging marine life, particularly phytoplankton.

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What is the significance of the Montreal Protocol?

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The Montreal Protocol is an international treaty established in 1987 to phase out the production and consumption of ozone-depleting substances, leading to the recovery of the ozone layer.